MarketingSherpa Summary - Why They Won:
Valentine's Day has become one of the most competitive in email marketing. Recipients' mail boxes are stuffed with look-alike offers from loads of retailers and spammers. We suspect the team behind this test must have been a bit worried that a second-try would be either ignored or annoying in all the Valentine's overload. Thank goodness they decided to test anyway. The results were worth it -- for everyone who reads about this entry.
(Hint: Do you have any clicked-but-didn't-convert segments you could test sending a second-chance email to?)

From Their Nomination Form:
First blast to Idea Art’s entire database of 72,188 previous customers. The second blast sent to a smaller audience of those 72,188 who opened the previous email but did not click – 9,060. The first blast to the entire database flat-lined a week later at $6,025 gross sales. A strategic decision was made to blast to those previous openers who had opened but not clicked using the same offer, using different creative in a follow-up blast. The following blast to this targeted audience eight times smaller than the first blast generated an additional $8,690 gross sales for a grand total of $14,715 gross sales for the Valentine’s Day promotion. Through this campaign we learned that timing and segmentation is everything. First blast: 72,188 names, 15.5% open rate, 14.3% clickthrough rate and $6,025 gross sales. Second blast: 9,060 names, 63.9% open rate, 4.9% clickthrough rate and $8,690 gross sales. Total gross sales: $14,715.